Integrated Applications - Transport in the Atmosphere-Vegetation-Soil Continuum - page 294

Table 8.5 Alternative water management scenarios that were analysed for Sirsa
District

Scenario Description Required action

1 Reference situation Business as usual

2 Increased crop yields (15%) Improved crop varieties, better nutrient

supply, effective pest and disease
control

3 Reduced seepage losses (25-30%) Lining and improved maintenance of

irrigation canals

4 Canal water reallocation (15%) Divert canal water from northern parts

to central parts

reallocation (Scenario 4) increased the uniformity of the groundwater recharge sub-
stantially. Ideally, these scenarios should be combined to increase water productivity
and improve sustainability in Sirsa District (Singh et al., 2006b ).

8.3.9 Satellite Data Assimilation
In this study, we used remote sensing and simulation modelling separately to derive
WP values. Remote sensing of ET , yield and WP may also be used to calibrate plant
and soil parameters of the crop and soil models. For instance, Jhorar et al. ( 2004 )
used remotely sensed evapotranspiration to calibrate soil hydraulic parameters.
Another way to beneit from both the information produced by generic simulation
models and remote sensing is by so-called data assimilation (Walker and Houser,
2001 ; Schuurmans et al., 2003 ; Pauwels et al., 2007 ; Vazifedoust et al., 2009 ). In this
method simulation models are updated with remote sensing information whenever
an observation is available. While adjusting the model state variables, both model
errors and measurement errors by remote sensing are taken into account. In this
integration of simulation models and remote sensing data, all information sources
are optimally used to improve regional water productivity analysis and crop yield
prediction.

8.4 Response to Heat Wave Conditions of the Energy and
Water Balance of Grassland and Forests
Observations suggest that in western Europe the length and intensity of prolonged
periods of above-average warm conditions in summer (heat waves) have increased in
the past century (Della-Marta et al., 2007 ). Land-atmosphere interactions may play
an important role (Seneviratne et al., 2006 ). Those interactions may be different for